Investigating the faesibility of thermoplastic starch blends for eco-friendly food packaging applications

Abstract

Food packaging is crucial in preserving the quality of food products, extending their shelf life, and protecting against deterioration of physical, chemical, and biological nature. Yet, there has been increased research into eco-friendly alternatives to petroleum-based plastic packaging owing to concerns about the adverse environmental effects of the materials used traditionally. Being plentiful, sustainable, biodegradable, and inexpensive, starches have become one of the most exciting biopolymer candidates for research. Thermoplastic starch, prepared through plasticization of native starch with water and small molecules called plasticizers, is one of the candidates for food packaging. In this review, the potential applications of thermoplastic starch blends in food packaging are considered based on the analysis of the influence of plasticizers on thermoplastic starch and mixing of thermoplastic starch with common and biodegradable polymers. Particular consideration is given to the mechanical, physical, thermal, and barrier properties of thermoplastic starch blends and the applicability of these blends in food packaging. Based on the findings from the reviewed literature, it is evident that the addition of polymers such as polyethylene, polypropylene, polystyrene, polyvinyl alcohol, and polylactic acid to thermoplastic starch significantly increases their mechanical, flexible, processing, and barrier properties. It has also been observed that despite being environmentally friendly due to their increased biodegradability and low dependency on synthetic plastics made from fossil sources, challenges remain in terms of moisture sensitivity, blend compatibility, thermal stability, and commercialization. Taking all factors into account, there is much potential for the utilization of thermoplastic starch blends in sustainable food packaging applications. Further advances in blend modification and manufacturing processes will serve to accelerate their commercial acceptance and contribute to the development of environmentally sustainable packaging systems.